Reverberators for use in wide band assisted reverberation systems
A multi-channel reverberation system has a substantially constant multi-channel power gain at audio frequencies and comprises multiple signal inputs, one for each input channel, a number of comb filter networks connected to each signal input, each comb filter network including a feed forward stage, a cross-coupling network cross-coupling the comb filters to increase the reverberation echo density, and multiple signal outputs, one for each output channel. Preferably the feed forward stage of each comb filter provides a substantially constant multi-channel power gain at audio frequencies and the cross-coupling matrix is an orthogonal cross-coupling matrix cross-coupling a number of single channel allpass comb filters, positioned immediately before or after the delay lines, to create a multi-channel allpass comb filter with a unitary transfer function matrix at all frequencies.
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Claims
1. A multi-channel reverberation system comprising:
- multiple signal inputs, one for each input channel;
- a number of feed back comb filter networks connected one to each signal input, each comb filter network including a feed forward stage to provide a substantially constant multi-channel power gain at audio frequencies;
- a cross-coupling network cross-coupling the comb filters to increase the reverberation echo density;
- and multiple signal outputs, one for each output channel.
2. A multi-channel reverberation system according to claim 1, wherein the feed forward stage of the comb filters provides a transfer function matrix which is unitary at each frequency in the audio range.
3. A multi-channel reverberation system according to claim 1, wherein the cross-coupling matrix is an orthogonal cross-coupling matrix cross-coupling a number of single channel allpass comb filters, positioned immediately before or after the delay lines, to create a multi-channel allpass comb filter with a unitary transfer function matrix at all frequencies.
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Type: Grant
Filed: Apr 15, 1996
Date of Patent: Mar 17, 1998
Assignee: Industrial Research Limited
Inventor: Mark Poletti (Wellington)
Primary Examiner: Curtis Kuntz
Assistant Examiner: Xu Mei
Law Firm: Woodard, Emhardt, Naughton, Moriarty & McNett
Application Number: 8/624,547
International Classification: H03G 300;